The present disclosure relates generally to well drilling operations and, more particularly, to a method and apparatus for ranging to a nearby well from ahead of the drill bit.
Well drilling and logging operations often require ranging measurements. Ranging measurements are taken at a reference point and detect electromagnetic, acoustic, nuclear or other emanations from a target. The ranging measurements may be used to identify, for example, the relative location or distance of the reference point from a known target, or to identify the location or distance of a target from a known reference. One common use of ranging is to allow a relief well to find a target blow-out well, follow the target blow-out well, and identify a suitable intersection point. Ranging measurements may be taken using a sensor located inside of a drill string, but they may be susceptible to interference from the drill string. For some ranging measurements, the drill string must be removed from the well prior to performing measurements in that well. Such tripping of the drill string before each ranging measurement, however, may be costly and time consuming.
While embodiments of this disclosure have been depicted and described and are defined by reference to exemplary embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.